Grumbacher Academy Watercolor - Indigo Hue, 7.5 ml tube

Pigment Information

This color contains the following pigments:

PBk7-Lamp Black

PB29-Ultramarine [Blue]

PV19-Quinacridone Violet

Pigment Name

PBk7-Lamp Black

Pigment Type

inorganic

Chemical Name

carbon

Chemical Formula

C

Properties

Lamp black is a very opaque, heavily staining black pigment that does not have much covering or tinting power. It is typically the most opaque black in watercolor form. Though a very pure black, it tends to muddy slightly in mixtures. Natural sources may be brownish or bluish in tone because of impurities. When used in oil paints, it is one of the slowest drying pigments, and should not be used in underpainting or applied in layers underneath other colors.

Permanence

Lamp Black is very lightfast and absolutely permanent. It is used in all techniques in permanent painting.

Toxicity

<p>Carbon itself is not considered hazardous, however other combustion products that are hazardous are often present as impurities when Lamp Black is produced from natural materials. For this reason, commercial preparations of the pigment should be considered slightly toxic. Avoid skin contact and inhalation. Where such impurities are present, Lamp Black is a possible human carcinogen.</p>

History

Lamp Black is a carbon based black traditionally produced by collecting soot (known as lampblack) from oil lamps. It has been used as a pigment since prehistoric times. It is the black found in Egyptian murals and tomb decorations and was the most popular black for fresco painting until the development of Mars Black.

Pigment Name

PB29-Ultramarine [Blue]

Pigment Type

inorganic

Chemical Name

complex silicate of sodium and aluminum with sulfur

Chemical Formula

Na8-10Al6Si6O24S2-4 or Na6-8Al6Si6O24S2-4

Properties

Ultramarine is the standard warm blue, a brilliant blue pigment that has the most purple and least green in its undertone. It has a moderate to high tinting strength and a beautiful transparency. Synthetic Ultramarine is not as vivid a blue as natural Ultramarine. Ultramarine dries slowly in oil and tends to produce clean, though granular, washes in watercolor. French Ultramarine mixes well with Alizarin colors in oil and watercolor form to create a range of purples and violets. It can dull when mixed with white in acrylic form, but mixes well with other colors. The shade varies based on manufacturer. Considered a great color for glazes, it is not suitable for frescoing.

Permanence

Ultramarine has excellent permanence, although synthetic Ultramarine is not as permanent as natural Ultramarine. It may discolor if exposed to acid because of its sulfuric content.

Toxicity

Ultramarine has no significant hazards.

History

The name for this pigment comes from the Middle Latin ultra, meaning beyond, and mare, meaning sea, because it was imported from Asia to Europe by sea. It is a prominent component of lapis lazuli and was used on Asian temples starting in the 6th century. It was one of the most expensive pigments in 16th century Europe, worth twice its weight in gold, and so was used sparingly and when commissions were larger. Ultramarine is currently imitated by a process invented in France in 1826 by Jean Baptiste Guimet, making blue affordable to artists and extending the range of colors on their palettes.

Pigment Name

PV19-Quinacridone Violet

Pigment Type

organic synthetic, quinacridone

Chemical Formula

C20H12N2O2

Properties

Quinacridone Red is a high performance, transparent pigment with an average drying time and uneven dispersal. It is another name for Quinacridone Violet (PV19) and Quinacridone Red (PR192). Quinacridone pigments have relatively low tinting strength in general. For this reason, quinacridone colors are often expensive, because more pigment is required in the formulation.

Permanence

Quinacridone Violet has excellent lightfastness and is considered the most lightfast organic pigment in this shade range.

Toxicity

Quinacridone Violet has no known acute hazards. Overexposure to quinacridone pigments may cause skin irritation. Quinicridone pigments contain a compound found to be a skin, eye, and respiratory irritant.

History

Although quinacridone compounds became known in the late 19th century, methods of manufacturing so as to make them practical for use as commercial pigments did not begin until the 1950s. Quinacridone pigments were first developed as coatings for the automotive industry, but were quickly adopted by artists.